May 21, 2010 -- Childhood is typically viewed as a carefree, happy time, but depression can occur even in preschoolers as young as age 3, according to a recent update.

For years, experts thought that young children would be too developmentally immature to experience depression, says Joan L. Luby, MD, a professor of psychiatry at Washington University in St. Louis School of Medicine, who has researched the topic for 20 years. She wrote an update for the journal Current Directions in Psychological Science.

In the mid-1980s, experts realized that grade-school children as young as age 6 could in fact have clinical depression -- not just temporary blues, but a serious mental health condition.

In the past 10 years, Luby and other experts have found it can occur in children as young as age 3.

Parents may wonder what the typical 3-year-old has to be depressed about, but Luby says it is not necessarily because something bad or stressful is occurring. "It's a brain disorder that, basically what our findings are showing, can arise as early as age 3 and not necessarily due to bad things happening in life."

Preschoolers' depression, like that affecting older people, she says, is genetically based and can be brought out by stressful events, although there are not always stressful events accompanying it.

Depression in preschoolers isn't common, but it definitely does occur, Luby says. "There have been estimates of 1% to 2%," Luby tells WebMD. "That is about the same as [the prevalence] for school age, up to age 13 or so. Then there is a rise."

Even though preschoolers' depression is not common, Luby says it's crucial to identify it early and treat it early, to smooth the course later. The symptoms aren't all the same as for adults, and experts are still studying the best treatments.

Recognizing Depression in Preschoolers

Parents may actually mistake a depressed child for a "good" child, Luby says. "Kids who are depressed aren't disruptive in their environment," she says. "They're the wheel that's not squeaky."

"Guilt is a big marker," she says. "If something goes wrong, they might look very sad, think it's their fault."

An inability to enjoy the typical play a preschooler enjoys is another warning sign, Luby says.

A general "lack of joy" about life also warrants investigation, she says. Preschoolers can also have changes in sleep and appetite and their activity level, compared to their playmates.

If symptoms persist over a period of a week or two, it's time to seek help, Luby says.

Among experts, she says, there is a question about whether the two-week duration of symptoms normally considered worrisome for adults -- and a signal that it's clinical depression, not just the temporary blues -- should apply to children.

She tells parents to seek help if their child's symptoms are intense and continue over a week or two, even if the symptoms are not constantly present over that time.

"Children have a natural buoyancy," she says, so the symptoms may come and go more than they might with adults.

Depression in Preschoolers: Seeking Help

Where should worried parents turn for help? "You could go to the pediatrician, but you might have to educate your pediatrician a bit," Luby says, noting that not all are aware that depression can strike as young as age 3.

Parents might also seek help from a mental health provider, she says.

Although antidepressant medication is a mainstay of treating adult depression, it should never be given to preschoolers, she says. "Absolutely not to medication," she tells parents. It's not been tested in young children.

"Psychotherapy is recommended," she says, "in the kids' case, play therapy."

Luby is in the process of testing a modified version of a treatment called Parent-Child Interaction Therapy or PCIT that was originally designed for children with a conduct disorder.

In PCIT, parents of children with conduct disorders are taught to work with the child to improve pro-social behavior and reduce negative behavior. Luby is testing a version that focuses on teaching parents to enhance a child's emotional development. The thought is that early changes in emotional development skills could help with the depression.

She is hoping that early intervention will prove more effective than waiting and that the gains will be sustained in later childhood. She is studying the approach with 300 children, including some with depression, some with other mental health issues, and some healthy comparison children.

Depression in Preschoolers: More Perspective

Early intervention for depression in preschoolers is crucial, says Bernadette Melnyk, PhD, RN, dean and Distinguished Foundation Professor in Nursing at Arizona State University, Phoenix, and an advocate for teens' and children's mental health. She reviewed the update for WebMD.

Parents should be aware that some young children with depression are initially misdiagnosed, she says. "Because young children with mood disorders can get restless, hyperactive, and irritable when depressed, misdiagnosis -- for example, ADHD -- is common," she says.

The risk of depression in preschoolers is higher, when parents have a history of depression, she says.

Ignoring or denying depression at any age is hazardous, Melnyk says. "It is critical to assess for and identify depression in children of all ages so that early interventions can be implemented."

SOURCES: Joan L. Luby, MD, professor of psychiatry, Washington University in St. Louis School of Medicine, St. Louis.